Abstract

Compulsive production of verse is an unusual form of hypergraphia that has been reported mainly in patients with right temporal lobe seizures. We present a patient with transient epileptic amnesia (TEA) and a left temporal seizure focus, who developed isolated compulsive versifying, producing multiple rhyming poems, following seizure cessation induced by lamotrigine. Functional neuroimaging studies in the healthy brain implicate left frontotemporal areas in generating novel verbal output and rhyme, while dysregulation of neocortical and limbic regions occurs in temporal lobe epilepsy (TLE). Our patient's compulsive versifying after seizure cessation may have occurred through disinhibitory facilitation following normalisation of left temporal activity, or via enhanced connections between neocortical and limbic areas due to reorganisation of cerebral networks as a result of longstanding seizure activity. Our case complements previous observations of emergence of altered behaviour with reduced seizure frequency in patients with TLE. Such cases support the notion that reduced seizure frequency has the potential not only to stabilise or improve memory function, but also to initiate complex, specific behaviour patterns, in patients with TEA or TLE.